Field
The invention relates to medical devices for treating vascular disease and, more particularly, to endoluminally deliverable lumbar ostia occlusion devices and methods of deploying the same.
Discussion of the Related Art
An aortic aneurysm is a widening of the aorta usually as a result of a weakening of the aortic wall. Continued widening of an aortic aneurysm can result in formation of an aneurysm sac, which ultimately can rupture. Aortic aneurysms can be treated with open surgery or by endovascular aneurysm repair (EVAR) using a stent graft. In EVAR, a stent graft is delivered endoluminally to “exclude” the aortic aneurysm by bridging and allowing blood flow between healthy portions of the aorta on opposite ends of the aneurysm.
While exclusion of the aneurysm sac is a primary goal of the stent-graft treatment, it is known that leaks or “endoleaks” of varying degree can nonetheless still occur after deployment of the stent graft resulting in complications. An endoleak is defined as a persistent blood flow outside the lumen of the stent graft but within an aneurysm sac or adjacent vascular segment being treated by the stent graft. Increased blood flow into the aneurysm due to endoleaks can cause enlargement of the aneurysm sac, which can increase pressure and can cause rupture.
Endoleaks can result from incomplete sealing between the stent graft and aorta. Endoleaks can also result from persistent patency or blood flow into the aneurysm sac due to retrograde or opposing blood flow from collateral vessels, such as lumbar arteries, inferior mesenteric artery, and other aortic branches “excluded” by the stent graft. This latter type of endoleak is commonly referred to as a “Type II” endoleak.
Repair of Type II endoleaks is routinely done via a transarterial or translumbar approach. Initially, Type II endoleaks were treated by doing single-vessel embolization of the feeding artery using a microcatheter, wherein the collateral branch vessel supplying the endoleak was selectively embolized with coils near the aneurysm sac. Recurrence of endoleaks, however, following such procedures is common and believed to be due to multiple vessels feeding the endoleak. In other words, when one or some of the vessels are embolized, other vessels may continue to feed the endoleak into the aneurysm sac.
Another approach to repairing type II endoleaks is via a translumbar approach, which involves embolizing the endoleak sac nidus to break the communication between the multiple arteries that supply the endoleak. Other methods of treating Type II endoleaks includes ligation or clipping of the arteries of concern.
It remains desirable to provide an improved device and delivery of the same for treating endoleaks, particularly Type II endoleaks, following or in connection with EVA.